Die tables



Aug. 26, 1958 F. P. HoPFELD DIE TABLES Filed Aug. ll, 1955 2 Sheets--Sheeil 1 zu .F'Z

Aug. 26, 1958 F, P. HoPFELD DIE TABLES Filed Aug. 1l,- 1955 2 Sheets-Sheet 2 n with!! HIM.. .HIHUHIJIIrmh United States Patent DIE TABLES Fred P. Hopfeld, Elmwood Park, Ill., assignor to Grand Specialties Company, Chicago, lll., a corporation of Illinois Application August 11, 195s, serial No. 527,850 ZClaims. (Cl. 187-17) This invention relates to a die table.

In production work on sheet metal or the like, resort is often had to so-called die tables for accommodating a vertical stack of sheets of metal, as in those instances where sheets of metal are to be advanced one by one from a supply stack in to a production machine for bending or stamping such sheets individually into the form desired. Usually it is desirable that such a die table be alforded as having a table top that may be selectively elevated so that the top-most sheet of the stack will be at the in-put level of the production machine, and the facilitation of this operation in a precise manner is the primary object of the present invention.

Under most circumstances, accurate positioning of sheets of metal as aforesaid is of importance if jamming, inaccurate feeding or the like is to be prevented, and heretofore such accuracy of in-put operation has not always been attained. Accordingly, another object of the present invention is to enable the table top of a die table to be elevated in such a way that assurance is had that all portions of the table remain in a true plane.

Other and further objects of the present invention will be apparent from the following description and claims and are illustrated in the accompanying drawings which, by way of illustration, show a preferred embodiment of the present invention and the principles thereof and what I now consider to be the best mode in which I have contemplated applying these principles. Other embodiments of the inventions embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.

In the drawings:

Fig. l is a perspective view of a die table constructed along the lines of the present invention;

Fig. 2 is a sectional view taken substantially on the line 2 2 of Fig. l;

Fig. 3 is a sectional view, broken away in part, takenl substantially on the line 3-3 of Fig. l;

Fig. 4 is a fragmentary View of a portion of the table TOP;

Fig. 5 is a side elevation of the die table with the table top in an elevated position; and

Fig. 6 is a fragmentary sectional view taken through the standard of the table.

In the drawings, the present invention is illustrated as embodied in a die table 20 which is fabricated entirely of metal, but if desired the top 21 of the table may be faced with wood, plastic or the like.

The table 20 includes a relatively heavy rectangular base 23 which as to dimensions corresponds substantially to the top 21 of the table. Fastening bolts as 24 are alorded at the four corners of the base 23, and such are used to anchor the die table in position of use.

The table top 21 n normal position reposes on a standard afforded by a pair of vertically disposed plates 27 2,349,085 Patented Aug. 26, 1958 and 28 as shown in Figs. 2 and 3. The side edges of these plates are tapered inwardly in an upward direction as shown in Fig. 1, and the lower edges thereof are welded to the base 23 so that the plates 27 and 28 are in parallel spaced relation affording a relatively wide cavity C, Fig. 3, therebetween.

Suitable bracing members in the form of rods 26 are welded at one end to the standard plates 27 and 28 and at the lower or opposite end to the base 23.

The die table of the present invention is to be used as a support for a vertical stack of individual sheets or blanks of metal that are to be fed one by one in to a production machine for fabricating such sheets individually as is well known in the art. lnasmuch as the sheets of metal are to be fed along a common in-put path with respect to such a production machine it is necessary that the table top 2l be arranged for elevation to differ ent heights so that the top-most sheet or blank of metal will be accurately disposed at the in-put level of the production machine.

To achieve this, a piston rod 30, Fig. 5, having a piston 30P, Fig. 3, operated by lluid under pressure is disposed between the plates 27 and 28 affording the standard of the table so as to act against the bottom of the table top 21 at the geometrical center point thereof. Thus, the piston 30P is normally reposed in a hydraulic cylinder 31 suitably anchored to the base 23 in the cavity C between the standard plates 27 and 28. A relatively narrow reinforcing plate 32 is fastened as by bolts to the underside of the table top 21 along what constitutes the longitudinal axis thereof, and a pair of spaced apart mounting plates 33, Figs. 4 and 5, are secured in spaced relation to the underside of the reinforcing plate 53. Disposed between the mounting plates 33 is a socket member 35 to which the upper end of the piston rod 30 is adapted to be connected as by a pin SSP, Fig. 5.

Fluid under pressure is adapted to be furnished through a conduit 40 to the lower end of the cylinder to act against the piston 30P and raise the table top 21 to the desired level and the working uid enabling this to be done is in the present instance supplied to the conduit 40 from a housing 42, Figs. l and 3, carried by an angle bracket 43 the vertical flange 44 of which is bolted to the outer face of the standard plate 28. A piston to for supplying tluid under pressure in a mechanical advantage relation to the piston 30P in the cylinder 31 is manually operated by a crank 46. To bleed the cylinder 31 when it is desired to lower the table top 21, a manually operated control arm 48 is afforded for the bleed valve of the usual kind.

It is of importance with respect to the feeding of the sheets of metal on the table top 21 that all portions of the table top 2l be maintained level in a true plane. To enable this to be accomplished in accordance with the present invention, a pair of guide members suitably in the form of I-beams Sil and 51 are arranged in equally spaced relation 011 either side of the piston rod 30 with the upper ends thereof welded to the underside of the reinforcing plate 31 as shown in Fig. 5. The I-beams 50 and 51 affording the guide members for the table top include vertical flange portions as SGF and SlF respectively and medial web portions as 50W and 51W.

top 21 reposes on the standard of the die table as shown in Fig. l, and under this circumstance the guide members 5G and 51 are telescoped or retracted fully within the cavity C between the standard plates, The edges of flanges SGF and SlF of the guides Sil and 5l are spaced inwardly of the inside faces of the vertical standard plates 27 and 28 as shown in Figs. 2 and 6, and to take up this slack and thereby assure that there will be no lateral play of the guides for the table top, shoes as .5.5, Figs. 2 and 5, are Welded to the lower ends of the I-beams on either side so as to slidably engage the opposed inner faces of the vertical standard plates 27 and 28 during elevation of the table top.

In like manner, shoes as 56 are welded to the inside faces of the standard plates 27 and 28 at the respective tops thereof in position to be slidably engaged by the side edges of the flanges SGF and'SlF of the guides 50 and 51 during elevation of the table top as can be best seen in Fig. 6. ln this way, assurance is had that during elevation of the table top 21 the guides 50 and 51 are maintained in true vertical planes as viewed in Fig. 2.

A pair of end plates 60 and 61, Fig. 6, are arranged between the standard plates 27 and 28 and are welded to the inner faces thereof, thus serving to reinforce the standard of the die table and to accurately space the standard plates 27 and 28. Elongated shoes in the form of bars 64 and are arranged medially of the end plates 60 and 61 on the inside faces thereof andare secured to the end plates 60 and 61 as by bolts 68, and the arrangement is such that the outward flanges 50F and 51F of the guides 50 and 51 slidably engage these members during elevation of the table top as in the instance of the shoes 55 and 56.

To assure that an incremental movement of one of the guides 50 or 51 during elevation of the table top is imparted equally to the other guide so that all portions of the table top 21 advance together in a common plane during elevation of the table top, equalizing means are extended between the guides 50 and 51, and in the present instance these equalizing means are in the form of a pair of chains and 71.

The chains 70 and 71 are arranged between the guide members 50 and 51 so that the end of one such chain is connected to the upper portion of one guide and then repeatedly reversed upon itself between the standard plates and then connected at the opposite end to the lower portion of the other guide member. This is attained by having resort preferably to rotatable idlers supported between the standard plates 27 and 28 and these idlers in the present instance are in thc form of a pair of upper idler pulleys 73 and 74 and a pair of lower idler pulleys 75 and 76. The idler pulleys are journaled on correspondingly spaced pairs of upper and lower axles as extended between the standard plates, and the pulleys are arranged on these axles so that the chains 70 and 71 may be extended between the respective guide members to travel in parallel opposed relation during elevation of the table top.

The pulleys 73 and 76 are disposed on the corresponding axles 80 adjacent the standard plate 27 and the other two pulleys are disposed on their axles to be adjacent the standard plate 2S thereby affording separate, spaced tracks for the two chains 70 and 71. The chain 70 is the one associated. with the pulleys 73 and 76 and is extended from the upper portion of the guide member 51 to the lower portion of the guide member 50. The particular way in which this is accomplished is to attach the chain 70 at one end to a lug 82 fixed to the inner ange of the guide 51 adjacent the top portion thereof. The chain 70 is then directed downwardly to the pulley 76 and then diagonally upwardly within the cavity C in the standard to the pulley 73 and from the pulley 73 downwardly to a lug 83 fixed to the lower end portion of the inner flange of the guide 50.

ln like manner, the chain 71 is the one associated with the pulleys 74 and 75 and is attached at one end to a lug 85 secured to the inner flange of the guide 50'adjacent the top portion thereof above the lug 83 to which the lower end of the chain 70 is attached. The chain 71 is then directed downwardly about the pulley 75 and then diagonally upwardly in opposed relation to the chain 70 within the cavity C in the standard to the pulley 74 and then downwardly to a lug 86 fixed to the inner flange of the guide 51 adjacent of the lower end thereof.

Due to the above described arrangement of the equalizing means 70 and 71, the two depending guide members at either side of the table top 21 are constrained to advance equal distances together to hold the table top level when elevating forces are applied to the table top 21 by the piston rod 30, and such assures that the sheets of metal or the like stacked on the table top are disposed in a true or level plane that will be coincident with the input path of the production machine with which the die table of the present invention is adapted to be used.

Hence, while I have illustrated and described the preferred embodiments of my invention, it is to be understood that these are capable of variation and modification, and I therefore do not wish to be limited to the precise details set forth, but desire to avail myself of such changes and alterations as fall within the purview of the following claims.

I claim:

l. A die table comprising a base member, a pair of vertically disposed plates anchored in relatively closely spaced relation on said base member and affording a relatively narrow cavity therebetween, a table top superimposed on the upper edges of said plates and extending outwardly of said plates for a substantial distance, hy-

. draulic cylinder and piston means disposed in the cavity between said plates and having the piston means thereof pivotally connected to the under-side of said table top to apply a vertical elevating force to the table top equally distributed with respect to the area thereof, at least a pair of vertical guide members disposed in said cavity and being attached to the under-side of the table top in equally spaced relation with respect to said piston means and having a slide engagement with said plates to stabilize the table top laterally during elevation thereof, idlers rotatably supported on the inside faces of said plates, and a pair of equalizing chains each respectively secured at one end to the upper portion of a corresponding one of said guide members and passed about said idlers with the opposite ends thereof each secured respectively to the lower portion of the other one of said guide members so that the vertical movement of each guide member is equally imparted to the other to hold the table top level at either end during elevation thereof, said chains crossing in-said cavity.

2. A die table according to claim 1 wherein the idlers are four in number including a pair of upper idlers anda pair of lower idlers, the upper idlers being diagonally arranged so as to be adjacent the inside face of a related plate and the lower idlers being diagonally arranged in llike manner and each upper idler being directly above each lower idler.

References Cited in the tile of this patent UNITED STATES PATENTS 1,350,087 Trapp Aug. 17, 1920 1,710,442 Warshaw Apr. 23, 1929 2,639,784 Strock May 26, 1953 FOREIGN PATENTS 59,475 Norway lune 13, 1938 

